Perks of Being a Lab Rat
by SparklingDashofEgypt
Summary: Seto has a proposition for Yami that leads down an interesting road. YamixSeto
1. Business Proposal

Chapter 1: Business Proposal

A limo arrived outside the Game Shop one afternoon. The chauffer exited and jogged around to open the door. A tall brunette male in a white suit unfolded his tall frame and stepped out. "Good luck, Mr. Kaiba."

"Thank you, Rolland." Seto nodded and strode to the shop door. The bell tinkled as he entered and a familiar face looked up from the cash register. "Mutuo."he acknowledged coolly.

"I'm sorry you came all this way, Kaiba, but we don't have any new cards." Yami replied, returning to the cash register.

"I'm not here for cards. I'm here to make you an offer." Seto lifted his briefcase onto the counter and unlocked it. He pulled out a contract and passed it to him.

Yami looked wary as he took the contract. He read through the first page, his eyes widening. "You want me to be a product tester for your company?"

"Yes. As much as I hate to admit it, you're one of the best duelists. I will pay you very well for your time."

"I don't know if I have time." Yami replied, doubfully. He went out of the room, calling, "Grandpa?"

Grandpa appeared at the door to the kitchen. "Yami, what is it?"

"Kaiba offered me a job at his company." Yami shrugged.

"What kind of job?" Grandpa was curious.

"Product tester. I really want to do it, but I don't want to make it hard on you." Yami looked disappointed.

"I think we can survive without you for a couple hours after school and on weekends. On one condition." Grandpa nodded.

"What's that?" Yami was relieved, not caring what the condition was.

"You have to keep up with your homework. If your grades slip, I'll pull the plug, pardon the pun." Grandpa smiled.

Yami grinned, giving his grandfather a hug. "I won't let you down." He promised.

"I know you won't." Grandpa patted his back. "Now go give him your answer."

Yami went back to the Game Shop. Seto had been examining merchandise with interest until he spotted him. "He says I can work for you on one condition. That I keep up my homework. He can only give me up for a couple hours each day. Do we have a deal?" Yami asked, holding out his hand.

Seto shook his hand, giving a small smile of satisfaction. "Sign the contract and we'll be set." He turned the paper around so it faced Yami. Yami signed the contract and Seto snatched it away, tucking it in his briefcase. "See you at KaibaCorp tomorrow after school. Go in and talk to the receptionist. Tell her you are a product tester. She will have security take you down to the lab."

"Lab?" Yami was surprised.

"It's where we test all of our products." Seto headed for the door.

"Kaiba?" Yami called, and Seto turned, scowling. Yami realized his mistake. "Mr. Kaiba, thank you for your offer."

"We may not be friends, but you were my first choice for the job." Seto replied, and left.

Yami dressed in a nice red dress shirt and black slacks after school and drove Grandpa's car to the KaibaCorp building. He entered and stopped at the reception desk. "My name is Yami Mutou. Mr. Kaiba is expecting me in his lab for his product testing." He explained.

"Leo!" the receptionist called to a tall man in a uniform. "Escort Mr. Mutou to the labs."

"Of course." Leo nodded. He gestured for Yami to follow him and led him to elevator. He pressed the call button and the doors opened. They entered and the doors shut behind them. Leo pressed the button marked B and the elevator began to descend.

They were silent for the ride until the doors opened and Leo led him to a set of metal doors. "Good luck." Leo said in parting.

"Thank you." Yami nodded and knocked on the door. Leo walked off.

A blond woman opened the door. "You must be Mr. Mutou, come in. We were expecting you." She greeted, stepping aside to let him in.

Yami entered, looking around. He was in an observation room with computers and monitors. A glass wall that dominated one side across from the door. On the other side of the glass was a wide room.

"You're late." A familiar voice disrupted Yami's thoughts. Seto had entered, carrying a familiar object: a duel disk.

"Sorry, I wanted to change from my uniform." Yami explained.

"Put this on." Seto handed him the duel disk.

Yami slid the disk on, surprised at how light it was. "New prototype?"

"Yes. Interactive. You can find the strengths and weakness of an opponent you have already faced." Seto explained.

"How does that work?" Yami was curious.

"It has a memory card that records every card played in a duel, so if you face that person again, you can find ways to beat them with your cards." Seto nodded.

"Wow, that is pretty cool." Atem nodded.

"Well, go in there and try it." Seto was impatient. "Unless you didn't bring your deck."

"I brought it." Yami fished out his deck and slid it expertly into the deck slot. "Who will be my first opponent?"

"Him." Seto gestured to the glass where Yami saw something he hadn't noticed before. A duel computer was at one end of the room. "I only have one duel disk, so you can only duel him until we build another one. Unless you're scared." Seto taunted, smirking.

Atem gave him a cocky grin. "Do you really think a duel computer scares me?"

"I would doubt your competence if it did." Seto gave him a small smile in return. "Go in and try it out. I'll be in here watching."

Yami stepped through a side door into the room beyond. The duel computer hummed to life, the life point counter reading 4,000 points.

"Good luck, Mutou." Seto said, through the microphone.

Not knowing what deck he would be facing, Yami took his deck out and shuffled it, putting it back in the slot.

The duel started and it only took Yami a few seconds to recognize the cards played against him. "Kaiba, you are having the computer use your own deck?" he asked, surprised.

"You need a powerful deck to test it out." Seto explained. "Besides, you're the only one who beat it."

"I can think of a few." Yami muttered.

"What was that?" Seto asked sharply, even though they both knew he heard it just fine.

"I said I can't think any." Yami said, louder.

"I thought so." Seto left him to duel the computer as a research assistant came in. "What is it?" he demanded, irritated.

"We are having problems getting the new duel disk to configure. It says error every time we put a card down." The assistant explained.

Seto sighed, pinching the bridge of his nose. "Fine. I'll check it out after this guy leaves."

"Thank you, sir." The assistant nodded his head and hastily retreated, shutting the door behind him.

Seto returned his attention back to the duel, admiring Yami's style from a duelist's perspective. The way he confidently played cards, the cocky grin when he played a brilliant move, the way his pants snug around the curve of his backside.

 _Woah, where did that thought come from?_ Seto wondered, shaking his head of the unwanted thought.

Yami finished the duel and returned to the lab. He had won the duel, of course, and his eyes were bright. "How was that?" he asked, doubtfully. "Did you get the data?"

"In order to find out if the new technology works, we have to test it multiple times." The assistant in the room spoke up, pushing his glasses up his nose as he examined Yami from his chair at a computer. "If it works, you should get strategies and be able to beat the computer better."

Yami nodded. "Do you want me to go back in there?"

Seto shrugged. "Unless you want to take a break."

"I'm fine." Yami nodded. He headed into the duel room.

As the two hours came to a close, Seto noticed that Yami's lightning fast draw was getting slower. "You okay, Mutou? You need a break?"

"No, I can finish out the duel." Yami panted. He drew a card, even though he just had. Sweat was pouring down his face, matting his hair. "I play-" He didn't finish the sentence as his eyes rolled back in his head. He dropped to the floor.

"I'll call for a doctor." The assistant said immediately, as Seto reached the door.

Seto burst through the door and knelt beside Yami, checking for a pulse. "Don't bother. I think he just overexerted himself. I'll take care of him. Shut down the computer. We're done for the day. Call Rolland."

Seto lifted Yami into his arms and carried him out a private exit where Rolland was waiting for him with the limo. He silently opened the back door and Seto gently set Yami down on the seat. "Turn on the air conditioner." He ordered.

"Yes, sir." Rolland hurried to the driver's door and blasted the air conditioner, pulling out of the KaibaCorp lot.

Yami seemed to cool off as they drove, but he hadn't come to. Seto found himself worried about the teen's condition, but he tried to convince himself it was purely professional.

The limo stopped in front of the mansion and Seto got out, lifting Yami out as well. He carried him inside, barking orders to his staff. "I need a bowl of water, a rag, and a fan."

"Yes, Mr. Kaiba." The maid scurried off and Seto headed upstairs.

He set Yami on a spare bed as the maid returned with the items. She set them up, leaving as quietly as she had come. Seto placed the wet rag on Yami's warm forehead and sat in the chair in the corner to wait, seething with anger.


	2. Face My Wrath

Chapter 2: Face My Wrath

Yami slowly woke up and found himself lying on a soft bed. Cool air caressed his warm skin and a piece of fabric was on his forehead. "Do you know how furious I am with you?" a voice asked quietly, his voice humming with anger.

Yami turned his head to the right and found Seto sitting in a chair. His look was furious, his eyes dark and dangerous. "What did I do this time?" he asked, amused.

"This isn't funny. You could have died." Seto inhaled through his nose, trying to calm himself. "What were you thinking?"

"You need to speak English. I have no idea what you're talking about." Yami frowned.

"What do you remember?" Seto's expression softened a little.

"Arriving at the labs and dueling the computer." Yami replied, confused.

"The first time?" Seto stood and went over. He removed the cloth from Yami's forehead.

"Was there more than one?" Yami's confusion deepened.

"That explains a lot." Seto replied dryly. "You dueled yourself unconscious."

Yami's eyes widened. "And why were you holding a bedside vigil?"

Seto lifted a shoulder. "Concern for my employee."

"Bullshit. How many employees do you do that for?" Yami raised an eyebrow. Seto said nothing, so he swung his legs off the bed and sat up. "Thank you for your hospitality. I will be going now." Yami stood.

Yami swayed a little and Seto hurried around the bed steady him. "I am not letting you go home until you are well. Sit down." He ordered.

Yami sighed and sat on the bed. "Can you get me a glass of water? With ice."

"Do I look like your butler?" Seto raised an eyebrow.

Yami raised an eyebrow as well, mirroring him. "No, but you not look like the type to stay by an employee's sick bed, either."

Seto smirked. "Fine. I will get you some water. But that doesn't mean I will always do it."

Seto headed out and returned to him with a glass of ice water. He smiled a little as he handed it over. "Don't drink it too fast."

Yami took a sip, closing his eyes as it soothed his thirst. "Thank you."

"No problem." Seto nodded. He headed for the door. "Rest and I'll give you a ride when you are ready."

"What about my Grandpa and Yugi?" Yami asked, concerned.

"I called them already. They are concerned, but understood you need to stay here until you're recovered."

"Where is here?" Yami looked around, but saw nothing familiar.

"My spare bedroom. I had to get you somewhere so you could rest. Now lie down." Seto ordered.

"Yes, sir." Yami snapped to attention and gave a mock salute. He laid down on the bed.

"Watch your smart mouth." Seto warned, smirking.

"Or what?" Yami challenged.

Seto said nothing, just stared at him. "Just watch it." He said quietly.

Yami wondered if Seto's plans would have them be more as rivals. The thought made his head spin and his heart race. The thought of his lips touching the teen's full mouth were intoxicating.

"Get some rest. I'll be in to check on you later." Seto headed for the door and shut it behind him.

Yami was soon asleep.

Yami awoke and found a set of clothes laid out for him on the chair. A note was on top from Seto saying that he might want to change given how much he sweated earlier.

Thinking that a shower was a wonderful idea, Yami got out of bed and headed for the bathroom. He felt stronger now and enjoyed the warm water cascading over his skin, washing away the sticky feel of sweat still on his skin.

Seto was waiting for him in the living room when he came down. He looked up as he approached. "Good, you found the clothes. You feel better?"

"Much, thanks." Yami nodded. "I have no way of getting home."

"Did you go to the office by car?" Seto asked, reaching for his microphone.

"Yeah, I left it in the parking lot." Yami gave a description of the car and handed the keys over.

Seto called Rolland, who arrived a few minutes later. "Please get Mr. Mutou's car out of the KaibaCorp parking lot."

"Yes, sir." Rolland left the house and returned ten minutes later. "Your car is out front, Mr. Mutou."

"Thanks." Yami headed to the door and Seto followed. "Thank you for showing hospitality to me."

"No problem." A small smile warmed the teen's face.

Yami lost all resolve and pulled Seto's face to his. Seto was surprised at first before he kissed back. Yami pulled back, panting. "I better go before this goes any farther. Shall I see you tomorrow?"

"Don't you want to take some time off to make sure you're 100%?" Seto asked, smiling a little.

"No, I need the money. Besides," Yami paused and met his eyes with a cocky grin. "I want to continue where we left off."

Seto watched as Yami left and called before he reached the car. "Yami?" Both noted that he used his first name. "You will take breaks after each duel. I don't want another vigil."

Yami nodded. "I'll remember that."

"And call me Seto." Seto surprised himself with this statement. He hadn't realized he was pondering it until he spoke. "After that kiss, we can't be just employer and employee."

"See you tomorrow, Seto." Yami nodded again and got in his car.

Goose bumps erupted on Seto's arms at the use of his name and he shivered. _Am I really going to date my rival?_ He thought. _If anyone I know has a chance to challenge me intellectually, it's him. And he is a good duelist._

Seto headed inside.


	3. Sexual Tension of the Highest Order

Chapter 3: Sexual Tension of the Highest Order

Weeks passes and Seto had finally managed to ready a second duel disk to test. He called Yami. "Tomorrow will be different. We will be testing a second duel disk." He told him.

"Good. You finally have the first one ready." Yami sounded relieved. "I miss facing the real deal. It's not the same as hearing your _witty_ comments from the sidelines." Yami teased, and Seto could hear the smirk in his voice.

"Me too." Seto frowned. "Wait, what do you mean by witty comments?" he demanded.

Yami laughed, making Seto's heart rate jump. "I'm just yanking your chain."

"Be at the lab tomorrow at the usual time. I look forward to our duel of wits." Seto found himself smiling.

"That'll be easy for one of us." Yami quipped, grinning.

"Watch it, Mutou." Seto growled playfully and hung up. He sat back, looking forward to the next day.

The next morning Yami arrived at the lab in his usual outfit, nervously fiddling with his collar. "Don't be nervous." He told himself.

The elevator opened and he went to the lab room. Seto was there and handed him the duel disk, sparing him a glance. "Ready?" he asked, slipping the new duel disk on his forearm.

"As ever." Yami nodded, slipping his duel disk on. He followed Seto out of the room into the other room. They went their separate ways, standing ten feet apart. They slid their decks into the slots and activated their duel disk.

The duel started and Yami won. Several duels later, the record was close to a tie and the sexual tension was high. Seto went over, removing his duel disk. He set it on a table and closed the remaining distance. Yami noticed a curious gleam in his eye as he was pushed gently against the wall, Seto's mouth capturing his.

Yami ran his hands through Seto's hair, gripping it as they kissed. He broke the kiss long enough to say, "The audience."

"You're dismissed." Seto ordered, not glancing in the direction of the glass wall.

"Yes, Mr. Kaiba." A female responded over the intercom, no doubt leaving to gossip.

Seto's lips moved down to Yami's neck, nipping there. Yami moaned, tightening his grip on the teen's dark hair.

Seto lifted shaking hands to the hem of Yami's shirt and Yami lifted his arms so he could remove it. Seto kissed Yami's chest as he worked the teen's belt. Soon the pants and boxers were gone, leaving only the collar around his neck. When Seto went to unbuckle it, Yami grabbed his hand to stop him. "No, leave it." He murmured softly. "Can I undress you?"

Seto nodded and allowed him to undress him. Once they were both naked, they stood there, appreciating each other's bodies. Seto moved first, pulling Yami close.

Afterward, they lay in a tangled mess of arms and legs on the floor. "How was that for you?" Seto asked, kissing Yami's bare shoulder.

"Mh." Yami sighed contentedly, half asleep. "Next time, you will be uke."

Seto's eyes widened. "With how much you enjoyed it, I guess I'll try it. Does that mean we'll go again sometime?"

Yami gave him a tired grin. "After you were so attentive of my desire, hell yes."

"If I wasn't, you wouldn't sleep with me anymore." Seto pointed out.

Yami tensed and Seto realized he'd said the wrong thing. Yami searched for his clothes and got to his feet, dressing. "You can find a new lab rat." He spat.

Seto watched Yami go to the door and go through it, slamming it. The windows rattled. He sighed.

A few days passed and Seto didn't hear from Yami and he didn't call. Seto was trying to find a way to repair his relationship with the teen.

An idea came to him and he picked up his office phone. He dialed the Game Shop and Grandpa answered it. "Mr. Mutou, this is Seto Kaiba."

"Ah, my best customer. How may I help you?" Grandpa chuckled.

"Do you need help at the shop?" Seto asked, checking his schedule.

Seto could almost see Grandpa's eyebrows raise in surprise. "But you own your own company." He pointed out.

"True, but I've always been interested in games and it would be interesting to hone my skills." Seto explained.

"And what skills would you have in working at a shop?" Grandpa asked.

"I know money. I made a lot of it and I know how to manage it." Seto replied.

"You can work a cash register?" Grandpa asked.

"I know how to make change. If you teach me how to use yours, then I can do it." Seto leaned back in his chair.

"I'll give you a chance. Come over and we'll give you something to do." Grandpa hung up.

Seto decided his suit was not an appropriate outfit for working at a shop, so he decided to stop at the mansion and change into a blue button-up shirt and slacks. He took a limo to the shop.

Yami looked up as the bell tinkled and snorted, rolling his eyes. "What are you doing here?" he growled.

"Your grandfather hired me." Seto replied, smirking at his reaction. Yami blanched.

"Grandpa wouldn't do that. You don't know anything about managing a shop." Yami challenged.

"Yeah, I only know running a large international company." Seto raised an eyebrow. "I know how to make money. Your grandfather knew that and decided to give me a chance."

Yami folded his arms across his chest. "Don't expect me to forgive you just because you took a job here."

Seto shrugged. "I'm not expecting anything. Do what you want."

Yami scowled. "I need to talk to my grandpa." Yami strode from the shop and found Grandpa in the living room. "How could you hire Kaiba?" he hissed.

Grandpa didn't seem concerned by Yami's reaction. "He knows business. And," He paused and leveled a look at the teen. "You two are good for each other. If you work together, you can patch things up."

"Patch things up?" Yami shouted angrily. "He's arrogant, pushy, rude. Everything I can't stand."

"Isn't there anything you like about him?" Grandpa asked.

Yami thought a moment. "I like his loyalty to his brother." He admitted.

"Remember that. And give him another chance." Grandpa advised.

"You're pretty smart, you know that?" Yami smiled.

"Well, age tends to do that." Grandpa grinned.

"You must be a genius, then." Yami teased.

"Watch it, boy. I'm not too old to put you over my knee." Grandpa growled playfully.

Yami laughed and headed back into the shop. Seto was examining the merchandise. "Is there anything not too demeaning for you to do?" he asked, smirking.

"No, give me whatever task you want." Seto shrugged.

"Okay, sweep the shop. If you can handle it." Yami smirked.

Seto grabbed the broom, a determined look on his face. He began sweeping as Joey, Tristan, and Tea entered the shop.

"Kaiba, doing servant's work?" Joey laughed. "I gotta see this."

"Shut up, Wheeler." Seto muttered, concentrating on the task.

"How many Kaibas does it take to screw in a light bulb." Joey continued, ignoring Seto. He didn't wait for an answer. "One to screw it in and one to go back in time to ask Edison how to do it!" Joey and Tristan howled with laughter.

"Clever. But at least I'm smart enough to invent a time travel machine. The only thing you'll invent is a self-filling beer hat." Seto sneered.

"Kaiba, stop it." Yami ordered, scowling.

Seto lifted his chin. "Now scamper along, puppy, the big boys have things to do."

Joey growled. "Shut up, Kaiba."

"Go watch TV. I have to work in the store." Yami ordered, pushing the trio out of the shop. He glared at Seto. "Why do you have to rile him?"

"He makes it so easy. Why do you care? You don't seem to want to be with me." Seto pointed out.

"Don't say it too loudly." Yami glanced nervously in the direction of the living room door.

Seto arched an eyebrow. "You ashamed of me?"

"That's not it." Yami shook his head. "They wouldn't understand what I see about you."

Seto approached cautiously, a smile on his face. "What do you see?"

Yami smiled. "I see a stubborn, arrogant, egotistical teen who also has a generous side."

Seto closed the distance between them and pulled Yami's mouth to his. Yami's mouth was still at first and then moved against his.

"Oh my God!" Tea cried from the door after a moment and Yami and Seto broke apart, looking guilty. Tea, Tristan, and Joey were in the doorway, staring wide-eyed at them.


End file.
